One of the challenges in obesity prevention is to motivate children to select lower fat (LF) foods. This is particularly difficult when the LF options must compete with an array of higher fat (HF), calorie dense entries. We have a range of pilot data that support a strategy of manipulating the menu mix of LF/HF foods and thus, the competition between LF &HF options. There is, however, a range of formative research that must occur prior to an RCT for this intervention strategy. A combination of qualitative and quantitative methods is proposed within a large, diverse group of elementary school children [7,000 students;65% minority and 47% low socioeconomic status (SES)] to understand food selections at school lunch. A partnership has been established with a large, independent school district (17 elementary schools) and their food service director to examine this issue of interest. In the first year of the proposal, we will conduct a secondary analysis of the district- generated entr[unreadable]e tracking system for each elementary child within this ethnically-diverse, independent school district. This will assess variation in participation rates across ethnicity, gender, and socioeconomic status, as a result of changes in the number of LF foods offered in the school lunch. For those who participate, we will also assess how variations in the menu mix (HF/MF/LF) impacts the selection of LF foods. The resulting data will identify the factors that affect selection of LF foods as well as how selection may vary with gender, ethnicity, and/or socioeconomic status. For the qualitative component, during Year 2, we propose several key informant interviews with school-based adults to develop a focus group guide for the student focus groups. Using the information derived from the adult interviews, we will complete a series of 12 focus groups (6 in a low SES school, 6 in a high SES school) designed to explore: 1) how children of different ethnicities decide amongst the foods offered for lunch, 2) how these foods compare to similar foods outside of school, and 3) what children would like to change in the menu. We will also conduct a series of taste tests to supplement the focus group information with quantitative data about food preferences. Consequently, food service directors will be better informed on how to manipulate menus that direct children to make healthier selections at school lunch, while also maintaining participation rates in the National School Lunch Program. Creating school menus that increase the probability of children making healthier selections has the potential for a larger, positive public health impact. PUBLIC HEALTH RELEVANCE: Understanding the factors that affect student food preferences across gender, ethnicity, and socioeconomic status is important in creating healthier school menus that appeal to children without reducing participation rates in the National School Lunch Program. A combination of qualitative and quantitative methods is proposed within a large, diverse group of elementary school children to understand food selections at school lunch.